664777990 has 8 divisors (see below), whose sum is σ = 1196600400. Its totient is φ = 265911192.

The previous prime is 664777963. The next prime is 664778003. The reversal of 664777990 is 99777466.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33238890 + ... + 33238909.

It is an arithmetic number, because the mean of its divisors is an integer number (149575050).

Almost surely, 2^664777990 is an apocalyptic number.

664777990 is a deficient number, since it is larger than the sum of its proper divisors (531822410).

664777990 is a wasteful number, since it uses less digits than its factorization.

664777990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66477806.

The product of its (nonzero) digits is 4000752, while the sum is 55.

The square root of 664777990 is about 25783.2889678567. The cubic root of 664777990 is about 872.7547289506.

The spelling of 664777990 in words is "six hundred sixty-four million, seven hundred seventy-seven thousand, nine hundred ninety".